History of Flight
On July 31, 2014, about 1930 central daylight time, an amateur-built Ketterling FEW P-51 Mustang airplane, registration N116LK, impacted an agricultural field after a loss of control near Lisbon, North Dakota. The pilot, the sole occupant, received fatal injuries. The airplane was destroyed by impact forces and a post-impact fire. The aircraft was registered to and operated by the pilot under 14 CFR Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan was filed. The local flight originated from Lisbon Municipal Airport (6L3) at an unconfirmed time.
Several witnesses provided accounts. One witness near the accident site reported seeing the airplane fly over the tree line northwest of her house, barely clearing the trees, followed by silence. She and her husband observed smoke and notified authorities. She described the airplane as very loud. Another witness heard the engine sound as if it were speeding up and slowing down. A third witness reported a loud unusual engine noise, then saw a light-colored low-wing airplane at about 500 to 750 feet traveling south. The engine made an abnormal sputtering noise that continued. The airplane lost altitude, nosed up slightly, rolled, and entered a slow spin. It went behind a tree line, and engine sounds ceased, followed by a large plume of smoke.
Personnel Information
The pilot, aged 64, held a private pilot certificate with a single-engine land airplane rating. He was issued a third-class special restriction airman medical certificate on April 22, 2014, with limitations requiring corrective lenses for near and distant vision and not valid for night flight or color signal control. His logbook was not reviewed, but he reported 700 total flight hours and 30 hours in the six months preceding his most recent medical examination.
Aircraft Information
The accident airplane was a 2/3 scale replica of a World War II North American P-51D fighter, constructed primarily of composite materials with a retractable conventional (tailwheel) landing gear and tandem seating. It was powered by a Chevrolet Corvette LS-1 engine through a propeller reduction drive. Kit manufacturer specifications included a wingspan of 25 ft 5 in, length 18 ft 6 in, max gross weight 2500 lb, fuel capacity 60 gal, and cruise speed 250 kts. Due to construction differences, the accident airplane may not have matched these specifications.
Meteorological Information
Weather conditions recorded at Gwinner Airport (GWR), about 14 miles south of the accident site, at 1029 were: wind from 330 degrees at 5 knots, clear skies, temperature 27°C, dew point 15°C, altimeter 30.04 inHg.
Wreckage and Impact Information
The airplane impacted a level wheat field about 3 nautical miles north of 6L3. All flight control surfaces were located at the wreckage site. The tail surfaces separated from the fuselage but remained largely intact. The left elevator separated from the horizontal stabilizer; the right elevator and rudder remained attached. The right wing and forward fuselage were almost completely consumed by fire. The left wing showed leading edge crushing and fire damage at the root. Flight control system examination revealed no pre-impact anomalies. The landing gear was retracted; flap position could not be conclusively determined but appeared retracted. The engine crankshaft could not be fully rotated due to crushing, but partial rotation confirmed continuity. Automotive ignition and fuel injection systems were extensively damaged, preventing testing.
Additional Data
The airplane was equipped with a Dynon SV-D700 primary flight display. The unit was sent to the NTSB Recorder Laboratory for data download. It recorded flight parameters from the attitude and heading reference system (AHRS) and GPS, but GPS data was unreliable. AHRS data showed the airplane took off from a pressure altitude of 1,097 ft and performed maneuvers exceeding 2 g in the first three minutes, with rolls to 80 degrees and vertical acceleration from 0.2 to 3.1 g. About 2 minutes before the end of recorded data, the aircraft was stable at 2,500 ft and 150 knots on a westerly heading. At 19:30:41, longitudinal acceleration turned negative, indicating deceleration, with lateral and vertical transients. Airspeed decreased to about 83 knots, and the aircraft turned left to a southerly heading. Altitude stayed steady for about 15 seconds, then decreased at 500–1,000 ft/min. The recording ended at 1,815 ft pressure altitude, descending at 626 ft/min at 78 knots. The manufacturer noted that sudden power interruption could result in loss of up to 30 seconds of data.
Medical and Pathological Information
An autopsy performed on August 1, 2014, by the University of North Dakota attributed the pilot's death to injuries from the accident. Toxicology testing by the FAA detected amlodipine (a calcium channel blocker) in the liver and kidney, and atorvastatin (a statin) in the liver.